Introduction: Cheap Artbots for Workshops
Hi there! My name is Allen Pan, and for the last year or so I've designed and presented public robotics workshops to literally hundreds of people in the city of Los Angeles. When I first started out, I was receiving a flat rate paid by the Library Foundation of Los Angeles from the Full Steam Ahead Grant. That meant that time, tools, and materials all had to fit within a pretty limited budget, and the expectation was that participants would get to take home whatever they made. It was tough, but I was able to put together a whole series of cost effective robotics workshops provided free to the public throughout the Los Angeles Public Library branches.
As I started getting more involved with the burgeoning (but sometimes slow) Maker Movement in Los Angeles, I found that educators, makerspaces, parents, and librarians were looking for resources for putting together their own Making themed workshops and events, and were often coming up short. A lot of projects they found on the internet were focused on one-offs that don't necessarily translate to a workshop environment, especially in regards to cost or prep time. So here's the first of hopefully several fully documented, fully budgeted, and fully workshoppable robotics projects. Enjoy!
Step 1: What the Heck Is an Artbot?!
Artbots (aka scribblebots, vibrobots, bristlebots, brushbots...) are a classic Maker beginner project where a vibrating motor causes a body (usually a cup) to shake and scooch along the ground on legs made of markers, thus leaving a colorful trail as it moves. Artbots use a simple circuit with a switch, a motor, and a battery and are very adaptable to almost any lesson plan or learning goal. You can focus on electricity, or balance for the younger ones, or even biology if you want to make artbots in the form of anatomically correct insects, bacteria, or other animals. Heck, you could probably bring these into a college class and start a pedantic debate about what counts as a "robot" or "art". The focus is up to you, and can potentially cover a wide range of STEAM topics. Technically, artbots are simple and forgiving, they lend themselves to open design, and aren't as paint-by-numbers as some other robotics platforms. Best of all, they are super affordable and don't require a lot of tools or prep work. For me, when running a series of workshops, artbots typically subsidize the more expensive robotics workshops.
Step 2: Shopping List
Here's a hopefully comprehensive list of all of the consumable materials needed for an Artbot workshop (I hope you have a Dollar Tree in your area!):
Cups ($1, makes 45): I go with styrofoam rather than plastic because the cups can be drawn on with the markers, and it muffles the vibrating sound a bit.
Battery holders ($0.75, makes 1): $0.65 if you're buying at least 10!
Masking Tape($1, makes...a bunch?): Try to have at least one roll for every three participants. So if you're expecting 15 people to show up, at least five rolls of masking tape. You can use other kinds of tape or adhesive, like hot glue guns, adhesive dots, sticky tack, etc, but I just go with masking tape because it's easy to tear.
Paperclips: Maybe you already have these! Otherwise you can grab them from wherever you can find paperclips, like Walmart or Office Depot. BEWARE! Some paperclips have a clear plastic on them that makes them useless for circuits, which are the kind that Dollar Trees around here have in stock. Also avoid colored paperclips.
Plastic Snack Baggies: You'll really need these to organize all the parts into ready-to-go "kits". You probably already have some on hand, but you can also get a pack of 30-50 from the Dollar Tree, or like a 100 if they're the fold-over kind.
Table Cover: These artbots need a surface to draw on, and while the markers are washable it's still a pain to have to scrub tables down. I usually use a white table cloth or poster paper, also from the Dollar Tree. If you have access to a roll of butcher paper, that would be ideal!
Wire Strippers: As of this writing they are on sale for $5 from Harbor Freight. You can probably find one in a hardware store for $10-$20. It's for prep, so you'll only need one if you're the only one doing prep work.
Scissors (optional): Some of the younger kids might not know how to tear tape yet. It's also nice to be able to cut things for the decorations. If you can get your hands on as many scissors as masking tape rolls, that works pretty well. Small safety scissors are sold 2 for $1 from Dollar Tree.
Cost Per Bot:
Assuming you're starting from absolute zero and only doing one workshop for 15 people, the total comes to less than $3.50 per Artbot (assuming you only get 1 tablecloth and the sale price stripper at Harbor Freight). If you've already got some of the materials and tools on hand (assuming you've got paperclips, tape, baggies, scissors, and wire strippers) the cost is more like $2.10 per Artbot. You can stretch this a bit further if you're expecting a larger crowd (15+) by enforcing one Artbot per household, since siblings often come together to these kinds of workshops.
As you can see, Artbots are extremely affordable per person even when starting from absolute scratch. Your library or classroom doesn't need anything else but tables and chairs to run this workshop.
Step 3: Preparation: the Toothbrush
The electric toothbrushes from Dollar Tree are marvels of Chinese engineering. You'll get a vibrating motor and a battery (and a spare toothbrush) for just a buck. I've attached a video of proper motor extraction technique. In short, you'll have to remove the bottom of the toothbrush and slam it down on a table a few times. You can do this on a sheet of cardboard to avoid denting the table. Regardless, and this should go without saying: don't do this on a nice dinner table.
Step 4: Preparation: the Battery Holder
This is the most tedious part of the prep work. I suggest putting a show on while doing this. The battery holder streamlines the workshop a lot, and allows younger kids to participate. If you're short on shipping time or prep time and your audience can handle it, you can try including 2 extra wires and taping them to the battery rather than using the battery holder. The chance of having a bad connection using that method is high though, and the last thing you want in a workshop is a dozen participants who all need help troubleshooting.
Step 5: Preparation: Wire
Nope, that's not electrical wire. Will it still conduct electricity? Yup. It might get a bit warm, and it's much easier to create a short since it isn't insulated, but the cost and prep time saved are worth it in my opinion. Having to cut lengths of insulated wire and then strip both ends adds a significant amount of prep time. By using bare wire you can just eyeball maybe 4" and cut, cut, cut. The packaging includes a cutter, too! Sometimes the package cutter can leave a pretty sharp end though, so you might want to just use the wire strippers or scissors you hate instead to get a smoother cut.
Step 6: Preparation: Bag the Kits
Alright, you've got a battery, a stripped battery holder, a de-toothbrushed motor, two paperclips, and a wire cut to about 4" for every man, woman, and child you're expecting to show up (plus one for yourself and maybe an extra or two, if you've got the money). Put the materials into plastic baggies as "kits" that you can hand out easily and quickly. Have a beer.
When setting up a room, I generally lay out all the shared materials like googly eyes, tape, and markers on the work table and hand out individual kits later once everyone settles into the room. You could probably even put the baggies into the cups and hand them out that way.
Step 7: Run the Workshop: Make the Motor Spin
Now, the information you cover (or don't cover) in this kind of workshop or event are entirely up to you, and will depend on your audience, the intent and context of the workshop, and your own personal presentation style. However, consider some of these points as you design and run your own Artbots workshop:
Safe Electricity vs Unsafe Electricity: Some people will be afraid of getting a shock. Others may leave the workshop thinking they can go around touching all kinds of other bare wires and batteries. It might be good to discuss the fact that the electricity in this workshop is "safe" to work with bare handed, and recommend in any other case to ask for the permission/supervision of an adult.
Key Terms: Electricity, Circuit, Voltage, Current, Power, Motor, Battery, Conductive, and probably a whole bunch of other words fit well into the workshop if you want to introduce the terms or concepts (Ooh, just thought of another one: Eccentric Weight). Even if you don't go into detail it would be good to be familiar with the correct usage of the vocabulary, just so you can be consistent and not mix up things like Power and Voltage, which can be easy in everyday talk.
Short Circuits: Odds are someone will create a short circuit and burn themselves. It might be good to warn them about when a short circuit can occur, what will happen if it does, and what to do about it. A short circuit is when electricity takes a short cut through a misplaced wire, if that happens the wire and battery can get very hot and even catch fire, so if you accidentally create a shortcut just quickly disconnect the wires.
And most importantly, get your audience using their hands ASAP. They came to your event to make something, not hear a lecture! They'll get more by thinking with their hands anyways. After a quick intro, I usually start by asking the group how they can use the battery to make the motor spin.
Step 8: Run the Workshop: It's a Circuit, Add a Switch!
By now in my workshops I've introduced the concept of a circuit, since the wires previously make a "circle" shape (circuit sounds like circle!). I ask about how they turn their lights on and off, and let them figure out the paperclip switch from there (with some scaffolding of course). If you go that route, all you need is for one person to get it and you can use them as an example, and even ask them to go around and help others. It may be easier given environmental and time constraints to create your own example circuit with a switch and have them follow step-by-step. Again, up to you how you'd like to present.
Step 9: Run the Workshop: Turn the Circuit On!
Note that there are different ways paperclips can be clipped. You'll get a much better connection if you cross them perpendicularly so that one paperclip is held down by the middle "tab" of the other. If you link them as in a paperclip chain, the connection will be poorer and you might get a weakly sputtering artbot. You can straight-up demonstrate this or scaffold (I notice that the motor spins faster when I press the paperclips together. Is there another way to connect the paperclips together so that the motor spins faster? etc).
Every so often, no matter how good the connection looks the motor just won't spin. It was smashed out of a dollar store electric toothbrush after all. That's why it's nice to bring a couple extra kits, in case a motor is doa or someone loses their wire or their paperclips. Two extras for every ten kits will do.
Step 10: Run the Workshop: Tape the Circuit to a Cup
So you've got a bunch of flailing vibrating circuits, now what? Well what would happen if you taped the motor and the battery to a cup? ("It's farting!" is something you'll hear a lot).
Note that the placement of the motor and battery do not have to be like this. If you have an example artbot though, most of the arbots will end up looking like the example. I haven't thought of a good way yet to illustrate the concept to an audience without having them all end up with a similar layout. Without an example the participants may not know what it is they're actually trying to accomplish while they're building, which is not ideal. But once they've seen one way to do it they'll usually do it that one way. The solution might be multiple, extremely different examples, but I haven't tried it.
Step 11: Run the Workshop: Decorate!
I limit markers to 3-4, and pipe cleaners to 3ish, and usually don't worry about the googly eyes too much (you get 125 for $1!). This is by no means an exhaustive list of decoration possibilities. Other decoration materials I've provided include glow sticks, colored popsicle sticks, clay, foam sheets, glitter, and bells for holiday themed artbots. Bring whatever you've got access to or strikes your fancy. At minimum though you need googly eyes, cause they're just great.
Unless you don't want to keep the left over materials, remind the participants that they can take home whatever they build, which does not include handfuls of pipe cleaners and markers. And that's it! Collect all your left over materials (including baggies!) and save them for another workshop. Crumple up your tablecloth or poster paper and try to fit it into a recycling bin as politely as possible.
Thanks for reading! Best of luck to those of you planning on running this, if you've got any questions leave a comment below and I'm sure someone will answer it ;)